Essential spectrum of local multi-trace boundary integral operators

Xavier Claeys

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arXiv · 1508.00556

Essential spectrum of local multi-trace boundary integral operators

Xavier Claeys

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Abstract

Considering pure transmission scattering problems in piecewise constant media, we derive an exact analytic formula for the spectrum of the corresponding local multi-trace boundary integral operators in the case where the geometrical configuration does not involve any junction point and all wave numbers equal. We deduce from this the essential spectrum in the case where wave numbers vary. Numerical evidences of these theoretical results are also presented.

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Xavier Claeys. 2015-08-03. Essential spectrum of local multi-trace boundary integral operators. https://arxiv.org/abs/1508.00556

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